1. Field of the Invention
The present invention relates to an apparatus for making a strip of fiber-containing rubber, more particularly to an extruder being capable of extruding a plurality of strips of fiber-containing rubber whose short fibers are oriented in the widthwise direction of the strip.
2. Related Art
In making rubber products such as pneumatic tire for example, for the purpose of reinforcing its rubber component, or providing a rubber component with anisotropy or the like, fiber-containing rubber compounds are sometimes used to make such rubber component or layer of the product. In making a pneumatic tire, sometimes, an unvulcanized rubber strip containing short fibers oriented in a specific direction is used to make a specific tire component. For example, using a strip including short fibers oriented in the widthwise direction thereof, a tread rubber can be made by winding the strip around a drum. If a relatively wide strip is wound while keeping the widthwise direction thereof almost parallel to the axis of the drum, the fibers in the tread rubber are oriented in the widthwise direction of the tread which may improve steeling stability without deteriorating ride comfort. If a relatively narrow strip is wound while keeping the widthwise direction thereof almost perpendicular to the axis of the drum, the fibers in the tread rubber are oriented in the radial direction of the tire which may improve road grip, traction, wet grip (on-the-ice performance) and the like.
It is therefore, an object of the present invention to provide an apparatus by which a plurality of rubber strips containing short fibers oriented in the widthwise direction thereof can be continually made at the same time, allowing for more efficient production and downsizing and simplifying of the apparatus.